I already own Starcraft 2 and, therefore, a Battlenet account. But I'm not playing it very often, so I let a friend of mine use it.

If I buy Diablo 3 (which I intend to do) and bind it to this very same Battlenet account, will we be able, my friend an I, to run these two games at the same time (on different computers, of course) ? Or should I create another Battlenet account (and prey for Blizzard to leave me the hell alone and not asking for an official identification on the rare occasions I connect to the two different Battlenet accounts with the same IP) ?